Part 1: Pathway engineeringIt is now accepted that fossil fuel reserves, the main source for liquid petroleum, will eventually be depleted. It is also established that the use of fossil fuels has a negative impact on the environment, contributing to global warming, through re-introduction of trapped carbon, a greenhouse gas, into the atmosphere. Thus an alternative source for liquid fuels needs to be found and one of the proposed alternatives is biofuels. Biofuels refers to technologies that employ living organisms, mostly yeast, algae or bacteria, to convert biomass to liquid fuels. Apart from the environmental benefits which come with biofuels, they may also contribute to the enhancement of energy security in countries which don’t have access to fossil fuel deposits, and offer a more profitable use of crops other than as a food source.